E600: 4.0-r17 to 4.1-r3 halves download speed

On 4.0-r17, my iPhone XR was pulling over 600Mbps. After flashing 4.1-r3 it can barely achieve 300Mbps. Upload speed seems unaffected. Tried a bunch of other iOS devices and one Surface laptop, all similarly impacted.

Reset AP and reconfigured manually from scratch: Problem persists.
Tried Problem persists.

Does anyone know what’s going on?

Can you please execute the following command on AP and can you validate the result one more time “receive-side-scaling”

That seems to have restored the previous level of performance. Was that something that was formerly on by default? If so, why was the default changed? Thanks.

Could you please upload tech-dump in case if you see changes in 4.0 to 4.1 default config next time.

Default values is updated as part of best practices.